Steam-engine for air-pumps



(No Model.) H. KRENTZ.

- STEAM ENGINE EOE AIE PUMPS.

No. 522,065. Patented June 26, 1894.

A "Mmmm [ffl UNITEDv STATES PATENT OEFICEQ HENRY KRENTZ, oFfsT. LoUis,rM1sso'UEi.

`STEAM-ENGINE FO`R AIR-PUMPS. vf SPECIFICATION formingpart of Letters Patent No.522,065, dated 1111x226, 18194.

Application tiled May 29, 1893.

To @ZZ whom it may concern:

Be it known that I, HENRY KRENTZ, of the city of St. Louis and State of Missouri, have invented certain new and useful Improve-A ments in Steam-Engines for Air-Pumps for Fluid-Pressure Brake Systems, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part hereof.

Myinvention relates to an improved steamengine for air pumps for fluid-,pressure brakesystems, and consists in the novel construction, combination and arrangement of parts hereinafter specified and designated in the claim.

The object ot' my invention is to simplify and cheapen the construction in this class of air pumps.

In the drawings: Figure ljis a vertical section of my improved air-pump. Fig. 2 is a top plan view of the same, with the steamchest cover removed. I Fig. 3 is a detail view in perspective of a rock-shaft and c onnections used in moving the slide-valve of the steam-cylinder.

1 indicates the steam-cylinder and 2 the cylinder of the air pump, which are both vertical with their bores in alignment and joined together by a center casting 3 which forms the upper head 4of the said air cylinder and the lower head 5 of the steam-cylinder. This center-casting is provided with an internal recess of any common shape which I designate by the numeral 6.

lI indicates the piston of the steam-cylinder, which is provided with suitable common packing-rings and located therein and rmly secured upon the upper end of the pistonrod 8.

9 indicates the piston of the air-cylinder, which is also provided with common packingrings and secured upon thelower portion of the piston-rod 8.

10 indicates suitable stuffing-boxes which encircle the piston-rod 8, and one is secured to the lower head 5 of the steam-cylinder and another is secured to the upper head 4 of the air cylinder and both project into the recess 6 of the casting 3, for anA obvious purpose.

11 indicates the upper head of the steamcylinder which is in the form of a horizontalplate having upper and lower parallel sur-l Serial No. 475,829. (No model.)

and the upper end of the port 15 communicates valso withthe interior of said steamchest, while its lower end communicates with the upper end of a steam-port 1S formed in the wall of the cylinder 1 and extending vertically therein and communicating with the lower end of the said cylinder.

A suitable steam pipe, or a pipe-connection 19 lis provided \for supplying steam to the steam-chest, and a` suitable exhaust pipe or exhaust connection 20 communicates with the exhaust port 16 to carry oft the exhaust-steam and discharge same atthe usual point. The interior of the steam-chest 17 is of sufficient size to contain and permit operation of the slide-valve 13 and its connections, and said chest is provided with a cover 21.

I desire to state that the steam-chest cover, the steam-chest, and the heads of the steam and air-cylinders are to be secured in position by common bolts or screws. The valveseat 12 is elevated so as to project upward within the steam chest a distance, and the same is rectangular in plan view as shown in Fig. 2. The shape of the slide-valve 13 in plan view corresponds to the shape 'of its seat, and said valve is constructed with the Vcommon exhaust-cavity 22, so as to admit steam alternately above and below the steam piston 7 and ralternately exhaust steam from above and below said piston, as said valve is moved upon its seat in a horizontal line transverselyv of the steam-cylinder, by the means presently described. The back of the slide-valve 13 is provided with a bearing 23 which extends transversely of said valve and has its upper side open.

24 indicates a rock-shaft mounted in suitable bearings 25 which project from the upper surface of the upper head 11 of the steam IOO cylinder, one at either side of the valve-seat within the steam-chest, and this shaft eX- tends transversely of said valve adjacent one end thereof.

26 indicates an arm having its lowerend fixed upon the shaft 24 intermediate of the bearings 25 so that said arm projects upward.

27 indicates a lever or arm having one end fixed to the shaft 24 and extending substantially at a right angle to said shaft and set substantially at a right angle to the arm 26 with its opposite end free, and so that its opposite end may vibrate and pass above and below the plane of the valve-seat, parallel to one side of said seat.

28 indicates a connecting-link or stirrup having a fork at each end. The fork at the inner end of said link 2S is provided with a pinor journal 29 `which engages and has a bearing in the bearing 23 on the back of the slide-Valve, while the fork at the opposite end of said link is provided with a pin 30 which engages a bearing 31 formed in the arm 26 adjacent the outer end of said arm, so that said link connects said arm 26 to the slidevalve. The piston-rod S is hollow or tubular `and has an open upper end.

32 indicates the valve operating-rod, the lower end of which is loosely mounted in the bore of the piston-rod 8 and is provided with a head or projection 33. The rod 33 is provided with a shoulder or projection 34A just below the under side of the upper head 11.

35 indicates a plate having an aperture 3G, and secured upon the upper side of the steam piston 7 by means of suitable bolts or screws 37, with its aperture engaging said rod, so that the plate 35 alternately strikes the head 33 and the shoulder 34 on said rod as said piston approaches the top or bottom of the steam-cylin der. The rod 32 extends upward in a vertical line through an aperture or passage 38 formed centrally of the bore of the cylinder in the upper head 11, and said rod projects upward above the slide-valve seat 12 and its upper end slides in a socket or bearing 39 formed in or attached to the steamchest cover 21. i

40 indicates a transverse slot formed in the rod 32 intermediate of its length, and this slot is loosely engaged by the lever 27, which is located therein loosely, so that said lever may oscillate and still be connected to said rod.

41 indicates the upper port of the air-cylinder 2 and 42 the lower port thereof. The inner end of the upper port 41 communicates with the aircylinder above the piston thereof, and the lower port 42 communicates with said cylinder below said piston. The outer ends of these ports are formed in separate necks 43, which are cast integral one upon or adjacent each end of the air-chamber and have vertical aligned faces at their outer ends. Separate valve casings 44 each carrying a suctionwalve 45, a delivery-valve 4G and a detachable-plug 47, are connected to the vertical faces ofthe necks 43. The suction and delivery-valves of each casin g are mounted in vertical alignment and are removable from their seats in said casing by detaching the plugs 47.

The operation is as follows: Steam from the boiler being admitted to the steam chest 17 through steam pipes 19, with the parts in the position here shown, enters the steam cylinder above the piston thereof by way of port 14, and drives said piston downward while the steam used onV the previous upstroke of said piston is discharged from beneath the same through the port 18 in the cylinder, the port 15 in the upper head thereof, the exhaust recess 22 in the slide-valve, the exhaust-port 16 in said head, and the eX- haust-pipe 20. As the steam piston nears the end of its downward stroke, the plate 35 carried thereby comes in contact with the head 33 carried by the rod 32 and draws said rod downward until the slide-valve cuts off the supply of steam through said port 14 on this downward stroke. The lover 27 has its free end thus carried downward, which rocks the shaft 24 and moves the free end of the arm 2G inward,and said arm carrying with it the link 28, moves the slide-valve 13 toward the right hand and first cuts off the supply of steam through the port 14, then the exhaust cavity 22 of the slide valve is brought over said port 14 and the steam used on this down` ward stroke is exhausted through said port 14, said exhaust cavity, the exhaust port 16 and the exhaust pipe 20. Meanwhile, at about the same time that the port 14 is placed in communication with the exhaust pipe, the slide valve uncovers the port 15 and again admits steam Vbeneath said piston, and so on. During the upward stroke of the steam-piston, as the same nears the limit of said-stroke, the plate 35 strikes the shoulder 34 of the rod 32 and throws the free end of the lever 27 upward, with aresult the reverse of that just stated when said rod is moved downward. The upward movement of the air-piston 9 causes the lower suction-valve 45 to lift from its seat, and causes air to be drawn through the series of straining apertures or holes 48 in the lower valve-casing beneath said suction valve, thence past the valve and through the port 42 into said cylinder. The downward movement of the air-piston closes the suction valve 45 just mentioned and drives the air contained in the cylinder below the piston out through the port 42 past the delivery valve 4G in the lower valve casing, by way of pipe connections 49 to the delivery pipe 50. In a similar manner, downward movement of the air piston draws air into the upp'er end of the cylinder through the upper port 41, past the upper suction valve 45, lifting the same. 'The air on the upper side of the air-piston is being forced outward through the upper port 41 during the upward stroke, and closes the upper suctionvalve 45 and opens the upper discharge IOO valve 46 and passes by way of pipe connection 51 to the same discharge pipe 50 to which the pipe connection 49 is connected.

The above described construction and relative arrangement of the separably detachable upper and lower valve casings, form a very desirable and convenient arrangement, as either of same may be detached without disturbing the other for purposes of repair, cleaning and the like. The valves -in each casing are detachable by upward movement by removing thc plug 47 which is located in alignment with the valves contained therein and above same.

What I claim is- In a steam-pump, the combination of two separate cylinders arranged vertically with their bores in alignment, one of the same being a steam cylinder, pistons located in said cylinders, a hollow piston rod connecting said pistons, a slide-valve seat, having steam and exhaust portsY and located upon the upper head of said steam cylinder with its face horizontal, a steam chest inclosin g said valve seat, a slide-valve mounted in said steam-chest upon said valve seat, said valve having a bearing for a pin or journal upon its back, a rock shaft 24 mounted in bearings within said steam-chest adjacent one end thereof, an arm 26 having its lower end fixed upon the shaft 24, a lever 27 having one end ixed to the shaft and extending at an angle thereto, a connecting-link connecting said arm 26 to the bearing on the back of the valve, a valve-operating rod 82, the lower end of which is loosely mounted in the hollow piston rod and provided with a head o r projection 33 therev in, a plate 35 having an aperture 36 and secured upon the upper side of the steam-piston with its aperture engaging said rod, a shoulder or projection 34 formed upon said rod just below the upper head of the steamcylinder in the path of said plate, said rod extending upward through an aperture or passage formed in the upper head of the steamcylinder and projecting upward in the said steam chest and provided thereat with a transverse slot 40, said lever 27 engaging said slot in said rod, and operative connections, substantially as herein specified.

. In testimony whereof I aflx my signature in lpresence of two witnesses.

HENRY KRENTZ.

Witnesses:

' EDWARD E. LONGAN,

J'No. C. HIGDON. 

